The nacelle of turbofan aircraft engines comprises right and left fan cowls covering internal parts of the engine that shall be operable to provide access to internal components of the engine for maintenance purposes.
WO 99/26841 describes a fan cowl which is a panel having a network of transverse and longitudinal beams which is manufactured draping composite material on a mold having the shape of the panel to be obtained and baking to polymerize.
EP 1 707 344 describes a method of manufacturing a monolithic fan cowl of composite materials with transverse and longitudinal beams of an omega-shaped cross-section.
A drawback of the fan cowls described in said documents is that the geometry of the longitudinal beams is not well adapted to the functional needs of the fan cowls with respect to the entry of loads.
A drawback of the manufacturing methods described in said documents is that they use, basically, uncured composite materials implying tolerances in the final surfaces of the fan cowl.